asm2wasm debuginfo

emcc.py

@@ -2103,6 +2103,8 @@ def do_minify(): # minifies the code. this is also when we do certain optimizati
           combined.write('\n//^wasm.js\n')
           combined.write(js)
           combined.close()
+        # normally we emit binary, but for debug info, we might emit text first
+        wrote_wasm_text = False
         # finish compiling to WebAssembly, using asm2wasm, if we didn't already emit WebAssembly directly using the wasm backend.
         if not shared.Settings.WASM_BACKEND:
           cmd = [os.path.join(binaryen_bin, 'asm2wasm'), asm_target, '--total-memory=' + str(shared.Settings.TOTAL_MEMORY)]
@@ -2130,10 +2132,24 @@ def do_minify(): # minifies the code. this is also when we do certain optimizati
             cmd += ['-g']
           if emit_symbol_map or shared.Settings.CYBERDWARF:
             cmd += ['--symbolmap=' + target + '.symbols']
-          cmd += ['-o', wasm_binary_target]
+          # we prefer to emit a binary, as it is more efficient. however, when we
+          # want full debug info support (not just function names), then we must
+          # emit text (at least until wasm gains support for debug info in binaries)
+          target_binary = debug_level < 3
+          if target_binary:
+            cmd += ['-o', wasm_binary_target]
+          else:
+            cmd += ['-o', wasm_text_target, '-S']
+            wrote_wasm_text = True
           logging.debug('asm2wasm (asm.js => WebAssembly): ' + ' '.join(cmd))
           TimeLogger.update()
           subprocess.check_call(cmd)
+          if not target_binary:
+            cmd = [os.path.join(binaryen_bin, 'wasm-as'), wasm_text_target, '-o', wasm_binary_target]
+            if debug_level >= 2 or profiling_funcs:
+              cmd += ['-g']
+            logging.debug('wasm-as (text => binary): ' + ' '.join(cmd))
+            subprocess.check_call(cmd)
           if import_mem_init:
             # remove and forget about the mem init file in later processing; it does not need to be prefetched in the html, etc.
             os.unlink(memfile)
@@ -2144,7 +2160,7 @@ def do_minify(): # minifies the code. this is also when we do certain optimizati
           cmd = [os.path.join(binaryen_bin, 'wasm-opt'), wasm_binary_target + '.pre', '-o', wasm_binary_target] + map(lambda p: '--' + p, shared.Settings.BINARYEN_PASSES.split(','))
           logging.debug('wasm-opt on BINARYEN_PASSES: ' + ' '.join(cmd))
           subprocess.check_call(cmd)
-        if 'interpret-s-expr' in shared.Settings.BINARYEN_METHOD:
+        if not wrote_wasm_text and 'interpret-s-expr' in shared.Settings.BINARYEN_METHOD:
           cmd = [os.path.join(binaryen_bin, 'wasm-dis'), wasm_binary_target, '-o', wasm_text_target]
           logging.debug('wasm-dis (binary => text): ' + ' '.join(cmd))
           subprocess.check_call(cmd)

tests/test_other.py

@@ -7315,6 +7315,36 @@ def test_binaryen_ctors(self):
       seen = run_js('b.out.js', engine=SPIDERMONKEY_ENGINE)
       assert correct == seen, correct + '\n vs \n' + seen
 
+  def test_binaryen_debuginfo(self):
+    if os.environ.get('EMCC_DEBUG'): return self.skip('cannot run in debug mode')
+
+    try:
+      os.environ['EMCC_DEBUG'] = '1'
+      for args, expect_dash_g, expect_emit_text in [
+          (['-O0'], False, False),
+          (['-O0', '-g1'], False, False),
+          (['-O0', '-g2'], True, False), # in -g2+, we emit -g to asm2wasm so function names are saved
+          (['-O0', '-g'], True, True),
+          (['-O0', '--profiling-funcs'], True, False),
+          (['-O1'], False, False),
+        ]:
+        print args, expect_dash_g, expect_emit_text
+        try_delete('a.out.wast')
+        cmd = [PYTHON, EMCC, path_from_root('tests', 'hello_world.cpp'), '-s', 'WASM=1'] + args
+        print ' '.join(cmd)
+        output, err = Popen(cmd, stdout=PIPE, stderr=PIPE).communicate()
+        asm2wasm_line = filter(lambda x: 'asm2wasm' in x, err.split('\n'))[0]
+        asm2wasm_line = asm2wasm_line.strip() + ' ' # ensure it ends with a space, for simpler searches below
+        print '|' + asm2wasm_line + '|'
+        assert expect_dash_g == (' -g ' in asm2wasm_line)
+        assert expect_emit_text == (' -S ' in asm2wasm_line)
+        if expect_emit_text:
+          text = open('a.out.wast').read()
+          assert ';;' in text, 'must see debug info comment'
+          assert 'hello_world.cpp:6' in text, 'must be file:line info'
+    finally:
+      del os.environ['EMCC_DEBUG']
+
   def test_wasm_targets(self):
     for f in ['a.wasm', 'a.wast']:
       process = Popen([PYTHON, EMCC, path_from_root('tests', 'hello_world.cpp'), '-o', f], stdout=PIPE, stderr=PIPE)

tools/ports/binaryen.py

@@ -1,6 +1,6 @@
 import os, shutil, logging
 
-TAG = 'version_26'
+TAG = 'version_27'
 
 def needed(settings, shared, ports):
   if not settings.BINARYEN: return False